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From: "Joerg Buchholz" <buchholz@hs-bremen.de>
Newsgroups: comp.soft-sys.matlab
Subject: int in R2008b, same integral?
Date: Fri, 12 Dec 2008 22:10:17 +0000 (UTC)
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Is there a mathematical reason, why R2008b can solve:

>> int ('1/sqrt(1-x^2)')
 
ans =
 
asin(x)

but cannot solve: 

>> int ('sqrt(1/(1-x^2))')
Warning: Explicit integral could not be found. 
> In sym.int at 64
  In char.int at 9
 
ans =
 
int((-1/(x^2 - 1))^(1/2), x)

Is there a way to make R2008b simplify 'sqrt(1/(1-x^2))' to '1/sqrt(1-x^2)'?